Simmons made his debut as Alphonso “Mack” Mackenzie in the Season 2 premiere, as part of newly installed Director Coulson’s expanded team. He went on to appear in every episode thereafter, though there was a moment just before the Season 2 finale when it appeared Mack had called it quits, saying he was unable to work for a man who was so alien-friendly.

But when colleague Bobbi went missing and with the Inhuman threat escalating, Mack stuck around to trap teleporter Gordon and help fight the good fight.